The weekend's blizzard was a natural disaster, meaning there is not much we could do to prevent or mitigate the storm's damage.

But I suspect we are contributing to the destructiveness of such winter storms by an action we take to reduce another risk of winter.

As I write this Sunday, four electrical trucks - two from Pennsylvania - are fixing power lines across the street. A big limb from a pine tree fell and took down the wires.

The crew chief said falling limbs and trees are responsible for the vast majority of outages in this storm - leaving several tens of thousands without power in Cape May and Atlantic counties alone.

Winds gusting well above 40 mph combined with wet, heavy, clinging snow to break limbs and topple whole trees, he said, in some cases taking utility poles with them.

This particular pine tree dropped a limb in January's storm, knocking out power then, too. Several other nearby pines the same age did not lose any limbs in either storm.

The problem pine has one characteristic that sets it apart from the others: The tree is very near the road.

This road, since Linwood's Seaview Avenue School is across the street, is salted frequently through winter to make traffic to and from the school safer.

Road salt can weaken trees and other plants.

When it leaches into the soil to the root zone, salt can block a plant's ability to absorb water, creating what botanists call a "physiological drought." Forestry professor Wayne Clatterbuck, of the University of Tennessee, said salt can even pull water out of plants as they try to maintain water and chemical balance.

Salt also reduces the ability of plants to absorb nutrients such as potassium, calcium and magnesium, with the sodium in the salt displacing these similar elements.

Salt damages trees nearest to roads, and occurs on the side toward the road. As it happens, that is also where power (as well as telephone and TV cable) lines are located.

Plenty of limbs and trees fall in winter storms without salt damage, no doubt. The rhododendrons in our back yard lost several branches, for example. But the holly tree out front, next to the road, dropped a limb, too - and it was on the road side.

A study quantifying the salt-damage factor in power outages would be welcome. But the lives saved by road salting means giving it up isn't an option.

Instead, we could reduce salt use by substituting sand for some of it. And we could use other kinds of salt that are less damaging to plants such as calcium chloride and magnesium chloride.

We can also irrigate the soil around roadside trees thoroughly in early spring to flush the salt from the root zone.

And, for the long term, we can choose trees that are more salt tolerant - such as oaks, cherries, black walnut, locusts, red cedars and Norway maples - for locations adjacent to roads.

With a little understanding and effort, we could minimize slippery driving conditions and costly power outages.

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The result for evergreens, especially those with a known susceptibility to salt such as pine and spruce, is that fewer needles are produced in spring and they drop prematurely. This reduces the tree's ability to use the sun to produce food, weakening it further.

On deciduous trees, salt injury makes leaves smaller and less productive, as well as damages flower buds and bark.